In manufacturing of semiconductor devices, wire bonding is used commonly in which electrodes on a semiconductor chip and electrodes on a substrate, for example, are connected electrically using wires. As an aspect of such a wire bonding technique, there is known a wedge bonding system in which a wire is connected to a bonding target without forming a ball at the tip of the wire. In such a wedge bonding system, a first bonding point and a second bonding point are connected using a wire, followed by the wire extending out of the tip of the bonding tool being cut at a portion, so that a wire tail for the next wire bonding is formed at the tip of the bonding tool, and the wire tail is bonded directly to the next first bonding point without a ball forming step.
Given the situation where the first bonding point is an electrode on a semiconductor chip, however, the tip of the wire tail after bonding to the first bonding point may come into contact with an adjacent electrode and/or a passivation film on the semiconductor chip, resulting in a damage to or a defect of the semiconductor chip.
In order to solve such a problem, there has been proposed a technique, as described in Patent document 1, for example, in which a member (mold) for bending the tip of a wire tail upward is provided and, before bonding to a first bonding point, the bonding tool is moved to above the member for arrangement of the shape of the wire tail, which requires the bonding tool to be moved with each wire bonding and thus is not exactly a simple and efficient manufacturing method. Alternatively, in view of the fact that such a problem can arise only at the first bonding point, it is conceivable to solve the problem through reverse bonding in which bonding is performed in reverse order, which disadvantageously puts a limitation on the order of bonding and thus is not exactly a wire bonding method of a high degree of design freedom.